Apparatus for practicing sighting and determining photographically the deviation errors



May 15, 1923.

O. MESSTER APPARATUS FOR PRACTICING SIGHTING AND DETERMININGPHOTOGRAPHICALLY THE DEVIATION ERRORS Filed May 29 gary, JanuaryPatented May 15, 1923.

UNITED STATES OSKAR MESSTER, OF BERLIN, GER-LIANY, ASSIGNOR TO N. V.AEEOFOTO, 0F

AMSTERDAM, NETHERLANDS, A FIRM.

APPARATUS FOR PRACTICING SIGHTING AND DETERMINING PHOTOGRAPHIGALLY THEDEVIATION EEPtOE-S.

Application filed May 29, 1919. Serial No. 300,766.

(GRANTED UNDER THE PROVISIONS OF THE ACT OF MARCH 3, 1921, 6:1 STAT. L,1313.)

To all whom it may concern Be it known that I, Osnen Mnss'rnn,manufacturer, a citizen of the German Republic, and residing at Berlin,Nos. 110111 Leipzigerstrasse, in the German Republic, have inventedcertain new and useful Improvements in Apparatus for Practicing Sightingand Determining Photographically the Deviation Errors (for which I havemade application for patent in Germany July 17, 1916, October 5, 1916,April 12, 1917; Austria, March 13, 1917; Denmark, January 23, 1919;Sweden, January 28, 1919; Netherlands, January 24, 1919; Hun- 27, 1919;and Switzerland, Aug. 16, 1919), of which the following is aspecification.

This invention relates in general to an apparatus for practicing aimingin the car of a flying machine and for determining photographically thedeviation errors made in firing at another flying-machine; in particularthe invention relates to means whereby the deviation errors of theoperator of a machine gun mounted upon the car of a flying machine maybe determined, in an apparent air-fight, for each shot fired by thepracticing persons. By the term firing I do not mean actual firing butmerely operating the trigger of the device hereinafter described. Forthat purpose the apparatus in question is constructed similar to anapparatus to taking photographic pictures, especially a so-called seriespicture-apparatus, and that apparatus is employed in lieu of the machinegun, but at the same place where this gun, when practically employed, ismounted in the car of the flying machine, and it serves to ascertain thequickness in the succession of the shots produced, in an air-fight, by amachine gun. The photographic apparatus for taking the pictures may be akinematographic apparatus, the wheel-work of which is driven either by aspring-work that normally is checked, or by an electromotor, and athread-cross is arranged in the field of View of that apparatus, and acontrivance for taking aim similar to that used in con nection withmachine-guns is arranged parallelly to the optical axis. This apparatusis operated by means of a small lever resembling the trigger of a gun,and as long as the lever or trigger is actuated kineniato pictures aretaken showing the quicl 3 the succession of the shotes of a machine gun.

Means are provided by which may be seen which of the two iiyers that areoccupied in an exercising fight and are fighting with each other hasfirst sighted the appuratus correctly, so that the superiority of one orthe other of them may be ascertained.

In order to make my invention more clear, I refer to the accompanyingdrawing, in which is shown a longitudinal section through an apparatusconstructed according to my invention. Referring to said figure, a isthe apparatus for taking photographic pictures which is constructedsimilar to a kinematographic apparatus; Z) is the contrivance for takingaim which resembles that of a machine gun and is arranged parallelly tothe optical axis of the kineniatographic apparatus; 0 is a smallelectromotor, which may be inserted into the circuit by a lever ortrigger (Z closing a switch 8. \Vhen the motor 0 is running, thefilmband e is moved, by the mediation of known means, in regularintervals corresponding to the quickness in the succession of the shotsof a machine gun.

Near to the picture window it is a doublearmed lever f fulcrumed at jthe upper arm of said lever is held in contact with the film-band bybolt 71 which is under spring pressure. Of course, an equivalent meansmay be employed for pressing the lever against the film band. The otherarm of the lever f is in contact with a spring g forming part of thecircuit containing the electromotor a. The electric source of current iscarried, as usually, in the car of the flying machines, and wiresconnect it with the apparatus in question. The film band forms a supportfor the upper arm of the lever 7'' so long as it is pulled by the roller71 off the roller m, but when the end of the film band leaves the rollerm, it can no more act as a support for the lever, in consequence ofwhich the bolt 2' forces the lower arm of the lever off the spring 9when the contact between the parts 7 and g, and thus also the circuit,will. be

broken so that the electromtor stops, and remains at rest, when thetrigger (Z is again actuated this operation again occurs.

The dial and the hands of a time-piece (not shown) situated at anappropriate place of the apparatus are arranged in the picture held ofthe latter, the object of this arrange ment being to allow of seeingwhich of the two fighting? fiyers has first sighted his apparatuscorrectly. The pictures taken allow of." ascertaining how the exercisingfight pro ceeded, at which place or places the apparatus has beensighted, how often the flyers have not sighted the apparatus correctly,and finally, considering also the space of time, as recorded. which ofthe two flycrs is to be considered as victorious.

Having now described my invention. what I desire to secure by a patentof the United. idtates is:

An apparatus for practicing sighting and determining photographicallythe deviation errors comprising a cylindrical casing hav ing end wallsclosing said casing and representing in contour a machine gun, a handleprovided at one end wall of said casing, a photographic apparatusarranged within said casing and including a lens carried by the otherend wall of the casing, a strip film feeding mechanism arranged withinsaid casing, an electric motor for actuating said film feedingmechanism, an electric circuit in which is included said motor, a switcharranged within said casing and included in said electric circuit, atrigger arranged adjacent said handle and operatively connected to saidswitch, a circuit breaker carried by said casing and included in saidelectric circuit, said circuit breaker comprising a spring pressedlever, a roller carried by said lever and adapted to rest upon said filmstrip whereby the circuit breaker will be kept closed and sighting meansarranged upon said casing parallel with the optical axis of saidphotographic apparatus whereby a series of pictures may be taken toascertain whether the apparatus has been sighted correctly.

In testimony whereof I aflix my signature.

()SKAR MESSTER.

